Apparently plenty of people think so. In one survey, 22% of "savvy" 8 to 17 year olds claim, "I don't give out my details online, I make up fake ones" according to Intersperience.

Creating an online persona can be one way to help protect yourself against the intrusions of a hyper-connected world.

Here are three times when an online alias is helpful:

1. You don't want everyone knowing your secrets.

It's no secret that search engines, websites and apps often track your activities and then use that information to target you for services or products they hope you may buy, or to serve up online ads.

While government agencies figure out how involved they want to be in protecting consumers' personal information, you can take some control by creating your alter ego for surfing the Net, signing up for coupons or online offers, etc.

2. You want to help protect yourself from identity theft.

If you thought it was just too easy for Melissa McCarthy to steal Jason Bateman's identity in the movie Identity Thief, think again. It's just not that hard for crooks to gather the info they need to impersonate someone else.

As my colleague Adam Levin has pointed out numerous times, most of us post way too much personal information online. All it takes is one incident where a site like Facebook gets hacked for a cyber thief to have all the information they need to steal your identity.

3. You want to get or keep a job. Whether you are currently employed, or hope to be, you may want to be cautious about what you post online. From the woman who was allegedly fired for posting on Facebook after she called in sick, claiming she needed to rest in a dark room, to the waitress who said she was fired after complaining about customers on her Facebook account, there are plenty of stories about employees who were fired over online posts.

Nearly two in five companies (37 percent) use social networking sites to research job candidates, according to a 2012 CareerBuilder survey. Another smaller survey by Reppler found that 69% of employers rejected a job applicant due to something posted on a social networking site.

High school students who are headed for college are apparently also wise to the risks of sharing too much info online and are changing their identities until their acceptance into college is confirmed.

Make up a name and supporting details. You can use an online random name generator or just make up a name of your choice. But just as a writer fleshes out the details of his or her characters beyond the name, you'll need to create some supporting details for the new you.

Since date of birth is a common identifier, it's a good idea to give your new persona its own birthday. You could choose your "half" birthday (6 months after you were born) or another day that has special meaning for you. (As a bonus, you may get coupons or other deals on that day, so you can celebrate twice a year!)

Get a new email address.

There are plenty of free email address services that you can use for this purpose.

Ideally use a computer or tablet dedicated to that identity.

If you use the same device for online searches and activities for both your real and fake identities, then it's likely that real information about you will spill over to the info gathered about your alter ego, and vice versa. The more you can separate the two, the better.

This system isn't perfect. For example, I signed up for a loyalty card from my local drugstore chain, but since it gives me discounts based on prescriptions I have filled at their pharmacy, I can't use my fake identity for that program. And if you are going to purchase something online, you'll need to do so using your real information so that you can use your credit or debit card, or Paypal account to pay for the purchase, and have it shipped to your real address.

It should go without saying that if you are creating a fake profile for any kind of unscrupulous or illegal activity, forget it: you can (and hopefully will) get caught. But when it does work, there is one distinct advantage to creating a whole new identity online. Unlike the real you, your fake one can always decide to just disappear. [Featured Products: Research and compare Identity theft protection plans at Credit.com]